Out-of-Plane Magnetic Anisotropy in Ordered Ensembles of FeyN Nanocrystals Embedded in GaN
Sprache des Titels:
Phase-separated semiconductors containing magnetic nanostructures are relevant systems for the realization of high-density recording media. Here, the controlled strain engineering of Ga?FeN layers with FeyN embedded nanocrystals (NCs) via AlxGa1?xN buffers with different Al concentration 0<xAl<41% is presented. Through the addition of Al to the buffer, the formation of predominantly prolate-shaped ?-Fe3N NCs takes place. Already at an Al concentration xAl? 5% the structural properties?phase, shape, orientation?as well as the spatial distribution of the embedded NCs are modified in comparison to those grown on a GaN buffer. Although the magnetic easy axis of the cubic ??-GayFe4?yN nanocrystals in the layer on the xAl=0% buffer lies in-plane, the easy axis of the ?-Fe3N NCs in all samples with AlxGa1?xN buffers coincides with the  growth direction, leading to a sizeable out-of-plane magnetic anisotropy and opening wide perspectives for perpendicular recording based on nitride-based magnetic nanocrystals.